"Today the challenge of political courage looms larger than ever before." Those words are likely as true today as they were when first penned by John F. Kennedy in 1955. In his book Profiles In Courage, Kennedy goes on to say, "Our political life is becoming so expensive, so mechanized and so dominated by professional politicians and public relations men that the idealist who dreams of independent statesmanship is rudely awakened by the necessities of election and accomplishment." Half a century has passed since JFK made this observation. What has been done to correct the problem? $1,500.

Lise Meiner and O.R. Frisch published their groundbreaking report on nuclear fission in the February 11, 1939 issue of Nature magazine. Frisch had suggested the term "fission" to describe the reaction as it reminded him of the division of living cells. The article is titled Disintegration of Uranium by Neutrons: a New Type of Nuclear Reaction. In response to their discovery, physicist Leo Szilard would note that he saw another, less pleasant direction than nuclear energy this development might lead to, an atomic bomb. Six years later, the atomic era would be launched in the closing days of the Second World War, and that deadly weapon still casts its shadow of fear over the world today. $2,200.